Dallol - The World's Weirdest Volcanic Crater

20 December 2011

In the North East of Ethiopia lies the Danokil Desert. At its heart is a volcanic crater, Dallol, little known and seldom visited but quite extraordinary.

Surrounding the volcano are acidic hot springs, mountains of sulphur, pillars of salt, small gas geysers and pools of acid isolated by salt ridges. It makes for one of the most bizarre landscapes on planet Earth.

Dallol is one of the most remote places on Earth and very few people live here. Little wonder. After all, who would wish to live in close proximity to such a vast and alien backdrop as this? Even the name, in the local language of the Afar people literally means disintegrated. Even today the volcano is not mentioned in most books on the subject of volcanology.

Not only that – Dallol is the record holder for the highest average temperature for an inhabited location. Recorded between 1960 and 1966 the average temperature is 34C (94F). The dazzling colors seen at the site, white yellow, green and red ocher, are due to the strong presence of sulphur, iron oxide, salt and other minerals.

People wishing to visit Dallol have two choices in terms of transport; firstly, they could hitch a lift on one of the camel caravans which passes the volcanic crater. Otherwise they must rent a 4WD vehicle from the nearby town of Mekele. Nearby, in Ethiopian terms, means a one day drive.

Dallol is effectively a volcanic explosion crater. It was formed when basaltic magma intruded in to salt deposits and water. This subsequently caused a huge phreatic eruption. The rising magma made contact with the ground water. As magma is so extremely hot the water evaporated immediately. The result was a huge explosion of rock, ash, water and steam – not to mention volcanic bombs (molten rock which cools and solidifies before it hits the ground).

The volcano last erupted in 1926 and gained some attention then but it had been known to Europeans for about two hundred years. Yet the site remained effectively unknown to most until recently – simply because of the hostile nature of the environment, the almost unbearable heat of the area and the very present danger from toxic fumes.

Haile Selassie's reign of Ethiopia, which came to an end in 1974, led to a decades long political instability which did nothing to encourage visitors. Coups, uprisings, drought and famine placed Ethiopia off the map for volcanologists and tourists alike during this period. The area in which Dallol lies was not open to foreigners until 2001 and even today an armed guard is perhaps advisable.

Incredibly, the site has not been designated a National Park or area of special scientific interest, yet this is under consideration at the moment. However, tensions between Ethiopia and nearby Eritrea together with local banditry mean that the site is only visited by a few hundred people each year. The age of adventure tourism has yet to really hit Dallol. Those who do visit still run the risk of being taken hostage in Ahmed Ela, the nearest village to the volcano.

The volcano is surrounded by a huge saline area, the edges of which are studded with a multitude of fairy chimneys where gases have broken through. The sulphuric hot springs bubble at boiling point. The salt of the Danokil Depression, 136.8 meters below sea level, mixes with volcanic minerals such as sulfur, to create terraces and unique, other worldly concretions. Geysers and chimneys adorn the site throughout.

Toxic gas regularly escapes from the numerous fumaroles and geysers, often without warning. Around the area the remains of small animals overcome by the fumes can be found. The gases do, however, also escape through permanent spurts – you can see them on the surface of the poison water pools, accompanied by a strange gurgling noise.

The fairy chimneys were formed when the Red Sea flooded the Danokil Depression. The passage of the sea created salt deposits around the volcano. Over thousands of years and helped by the evaporation of water combined with the absence of wind, these fairy chimneys formed in to their current perplexing shapes.

Only the most dedicated volcanologists and adventure tourists make it as far as this amazing place. However, the damage some have done (however inadvertently) to the delicate structures here is already noticeable. Although access to the site is becoming safer and more secure, perhaps the isolation of Dallol from the rest of the world is not such a bad thing after all.